Chamber Systems For Additive Manufacturing

ABSTRACT

A method of additive manufacture is disclosed. The method may include creating, by a 3D printer contained within an enclosure, a part having a weight greater than or equal to 2,000 kilograms. A gas management system may maintain gaseous oxygen within the enclosure atmospheric level. In some embodiments, a wheeled vehicle may transport the part from inside the enclosure, through an airlock, as the airlock operates to buffer between a gaseous environment within the enclosure and a gaseous environment outside the enclosure, and to a location exterior to both the enclosure and the airlock.

CROSS REFERENCE TO RELATED PATENT APPLICATION

The present disclosure is part of a continuation of U.S. patentapplication Ser. No. 15/336,485, filed Oct. 27, 2016 and claiming thepriority benefit of the below-listed provisional applications.

U.S. Patent Application No. 62/248,758, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,765, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,770, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,776, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,783, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,791, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,799, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,966, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,968, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,969, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,980, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,989, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,780, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,787, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,795, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,821, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,829, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,833, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,835, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,839, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,841, filed on Oct. 30, 2015,

U.S. Patent Application No. 62/248,847, filed on Oct. 30, 2015, and

U.S. Patent Application No. 62/248,848, filed on Oct. 30, 2015, whichare incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure generally relates to additive manufacturing and,more particularly, to powder bed fusion additive manufacturing chamberdesigns with high throughput capabilities.

BACKGROUND

Traditional component machining often relies on removal of material bydrilling, cutting, or grinding to form a part. In contrast, additivemanufacturing, also referred to as three-dimensional (3D) printing,typically involves sequential layer-by-layer addition of material tobuild a part. As more industrial sectors adopt additive manufacturingfor product innovation or mass-production tools, limitations ofefficiency and throughput remain challenging to overcome. Contemporarypowder bed fusion additive manufacturing systems are often operated in abatch-mode style to print an object in a build chamber. Once a print jobis completed, a substantial amount of time can be required to move partsto other areas or processing chambers for further work.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present disclosureare described with reference to the following figures, wherein likereference numerals refer to like parts throughout the various figuresunless otherwise specified.

FIG. 1A illustrates an additive manufacturing system;

FIG. 1B is a top view of a structure being formed on an additivemanufacturing system;

FIG. 2 illustrates an additive manufacturing method;

FIG. 3A is a cartoon illustrating an additive manufacturing systemincluding lasers;

FIG. 3B is a detailed description of the light patterning unit shown inFIG. 3A;

FIG. 3C is one embodiment of an additive manufacturing system with a“switchyard” for directing and repatterning light using multiple imagerelays;

FIG. 3D illustrates a simple mirror image pixel remapping;

FIG. 3E illustrates a series of image transforming image relays forpixel remapping;

FIG. 3F illustrates an patternable electron energy beam additivemanufacturing system;

FIG. 3G illustrates a detailed description of the electron beampatterning unit shown in FIG. 3F;

FIG. 4 is a perspective, partially cut-away, schematic diagram of oneembodiment of a machine for executing a process of additive manufacturein accordance with the present invention;

FIG. 5 is a perspective, partially cut-away, schematic diagram of analternative embodiment of a machine for executing a process of additivemanufacture in accordance with the present invention;

FIG. 6 is a perspective, schematic diagram of one embodiment of anenclosure for controlling a working environment surrounding multiplemachines contained within the enclosure in accordance with the presentinvention;

FIG. 7 is a schematic diagram of one embodiment of a manufacturingfacility including an enclosure containing multiple work zones inaccordance with the present invention;

FIG. 8 is a schematic diagram of an alternative embodiment of amanufacturing facility including multiple enclosures that eachcontaining a different work zone in accordance with the presentinvention;

FIG. 9 is a schematic diagram of another alternative embodiment of amanufacturing facility including multiple enclosures or work zonesarranged in a sequential configuration in accordance with the presentinvention;

FIG. 10 is a schematic diagram of another alternative embodiment of amanufacturing facility including multiple enclosures or work zonesarranged in hub-and-spoke configuration in accordance with the presentinvention;

FIG. 11 is a schematic diagram of another alternative embodiment of amanufacturing facility including multiple enclosures or work zonesarranged with connecting paths for both sequential and hub-and-spokeconfigurations in accordance with the present invention;

FIG. 12 is a schematic diagram of one embodiment of a wheeled vehicle inaccordance with the present invention; and

FIG. 13 is a schematic diagram of an alternative embodiment of a wheeledvehicle in accordance with the present invention.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanyingdrawings that form a part thereof, and in which is shown by way ofillustrating specific exemplary embodiments in which the disclosure maybe practiced. These embodiments are described in sufficient detail toenable those skilled in the art to practice the concepts disclosedherein, and it is to be understood that modifications to the variousdisclosed embodiments may be made, and other embodiments may beutilized, without departing from the scope of the present disclosure.The following detailed description is, therefore, not to be taken in alimiting sense.

The present disclosure describes a method of additive manufacture thatinvolves creating, by a first machine contained within a firstenclosure, a first part. The first part can be formed by a first processthat includes using a patterned energy beam, wherein the first part hasa weight greater than or equal to 2,000 kilograms. A first gasmanagement system is used to maintain gaseous oxygen within the firstenclosure below atmospheric levels. A first part can be transported frominside the first enclosure through an airlock. The airlock operates tobuffer between a gaseous environment within the first enclosure and agaseous environment outside the first enclosure, and to a locationexterior to both the first enclosure and the airlock. During thistransport process, the weight of the first part is continuouslysupported.

An additive manufacturing system is disclosed which has one or moreenergy sources, including in one embodiment, one or more laser orelectron beams, positioned to emit one or more energy beams. Beamshaping optics may receive the one or more energy beams from the energysource and form a single beam. An energy patterning unit receives orgenerates the single beam and transfers a two-dimensional pattern to thebeam, and may reject the unused energy not in the pattern. An imagerelay receives the two-dimensional patterned beam and focuses it as atwo-dimensional image to a desired location on a height fixed or movablebuild platform (e.g. a powder bed). In certain embodiments, some or allof any rejected energy from the energy patterning unit is reused.

In some embodiments, multiple beams from the laser array(s) are combinedusing a beam homogenizer. This combined beam can be directed at anenergy patterning unit that includes either a transmissive or reflectivepixel addressable light valve. In one embodiment, the pixel addressablelight valve includes both a liquid crystal module having a polarizingelement and a light projection unit providing a two-dimensional inputpattern. The two-dimensional image focused by the image relay can besequentially directed toward multiple locations on a powder bed to builda 3D structure.

As seen in FIG. 1, an additive manufacturing system 100 has an energypatterning system 110 with an energy source 112 that can direct one ormore continuous or intermittent energy beam(s) toward beam shapingoptics 114. After shaping, if necessary, the beam is patterned by anenergy patterning unit 116, with generally some energy being directed toa rejected energy handling unit 118. Patterned energy is relayed byimage relay 120 toward an article processing unit 140, typically as atwo-dimensional image 122 focused near a bed 146. The bed 146 (withoptional walls 148) can form a chamber containing material 144 dispensedby material dispenser 142. Patterned energy, directed by the image relay120, can melt, fuse, sinter, amalgamate, change crystal structure,influence stress patterns, or otherwise chemically or physically modifythe dispensed material 144 to form structures with desired properties.

Energy source 112 generates photon (light), electron, ion, or othersuitable energy beams or fluxes capable of being directed, shaped, andpatterned. Multiple energy sources can be used in combination. Theenergy source 112 can include lasers, incandescent light, concentratedsolar, other light sources, electron beams, or ion beams. Possible lasertypes include, but are not limited to: Gas Lasers, Chemical Lasers, DyeLasers, Metal Vapor Lasers, Solid State Lasers (e.g. fiber),Semiconductor (e.g. diode) Lasers, Free electron laser, Gas dynamiclaser, “Nickel-like” Samarium laser, Raman laser, or Nuclear pumpedlaser.

A Gas Laser can include lasers such as a Helium-neon laser, Argon laser,Krypton laser, Xenon ion laser, Nitrogen laser, Carbon dioxide laser,Carbon monoxide laser or Excimer laser.

A Chemical laser can include lasers such as a Hydrogen fluoride laser,Deuterium fluoride laser, COIL (Chemical oxygen-iodine laser), or Agil(All gas-phase iodine laser).

A Metal Vapor Laser can include lasers such as a Helium-cadmium (HeCd)metal-vapor laser, Helium-mercury (HeHg) metal-vapor laser,Helium-selenium (HeSe) metal-vapor laser, Helium-silver (HeAg)metal-vapor laser, Strontium Vapor Laser, Neon-copper (NeCu) metal-vaporlaser, Copper vapor laser, Gold vapor laser, or Manganese (Mn/MnCl₂)vapor laser.

A Solid State Laser can include lasers such as a Ruby laser, Nd:YAGlaser, NdCrYAG laser, Er:YAG laser, Neodymium YLF (Nd:YLF) solid-statelaser, Neodymium doped Yttrium orthovanadate(Nd:YVO₄) laser, Neodymiumdoped yttrium calcium oxoborateNd:YCa₄O(BO₃)³ or simply Nd:YCOB,Neodymium glass(Nd:Glass) laser, Titanium sapphire(Ti:sapphire) laser,Thulium YAG (Tm:YAG) laser, Ytterbium YAG (Yb:YAG) laser, Ytterbium:2O₃(glass or ceramics) laser, Ytterbium doped glass laser (rod, plate/chip,and fiber), Holmium YAG (Ho:YAG) laser, Chromium ZnSe (Cr:ZnSe) laser,Cerium doped lithium strontium (or calcium)aluminum fluoride(Ce:LiSAF,Ce:LiCAF), Promethium 147 doped phosphate glass(147Pm⁺³:Glass)solid-state laser, Chromium doped chrysoberyl (alexandrite) laser,Erbium doped anderbium-ytterbium co-doped glass lasers, Trivalenturanium doped calcium fluoride (U:CaF₂) solid-state laser, Divalentsamarium doped calcium fluoride(Sm:CaF₂) laser, or F-Center laser.

A Semiconductor Laser can include laser medium types such as GaN, InGaN,AlGaInP, AlGaAs, InGaAsP, GaInP, InGaAs, InGaAsO, GaInAsSb, lead salt,Vertical cavity surface emitting laser (VCSEL), Quantum cascade laser,Hybrid silicon laser, or combinations thereof.

For example, in one embodiment a single Nd:YAG q-switched laser can beused in conjunction with multiple semiconductor lasers. In anotherembodiment, an electron beam can be used in conjunction with anultraviolet semiconductor laser array. In still other embodiments, atwo-dimensional array of lasers can be used. In some embodiments withmultiple energy sources, pre-patterning of an energy beam can be done byselectively activating and deactivating energy sources.

Beam shaping unit 114 can include a great variety of imaging optics tocombine, focus, diverge, reflect, refract, homogenize, adjust intensity,adjust frequency, or otherwise shape and direct one or more energy beamsreceived from the energy source 112 toward the energy patterning unit116. In one embodiment, multiple light beams, each having a distinctlight wavelength, can be combined using wavelength selective mirrors(e.g. dichroics) or diffractive elements. In other embodiments, multiplebeams can be homogenized or combined using multifaceted mirrors,microlenses, and refractive or diffractive optical elements.

Energy patterning unit 116 can include static or dynamic energypatterning elements. For example, photon, electron, or ion beams can beblocked by masks with fixed or movable elements. To increase flexibilityand ease of image patterning, pixel addressable masking, imagegeneration, or transmission can be used. In some embodiments, the energypatterning unit includes addressable light valves, alone or inconjunction with other patterning mechanisms to provide patterning. Thelight valves can be transmissive, reflective, or use a combination oftransmissive and reflective elements. Patterns can be dynamicallymodified using electrical or optical addressing. In one embodiment, atransmissive optically addressed light valve acts to rotate polarizationof light passing through the valve, with optically addressed pixelsforming patterns defined by a light projection source. In anotherembodiment, a reflective optically addressed light valve includes awrite beam for modifying polarization of a read beam. In yet anotherembodiment, an electron patterning device receives an address patternfrom an electrical or photon stimulation source and generates apatterned emission of electrons.

Rejected energy handling unit 118 is used to disperse, redirect, orutilize energy not patterned and passed through the energy pattern imagerelay 120. In one embodiment, the rejected energy handling unit 118 caninclude passive or active cooling elements that remove heat from theenergy patterning unit 116. In other embodiments, the rejected energyhandling unit can include a “beam dump” to absorb and convert to heatany beam energy not used in defining the energy pattern. In still otherembodiments, rejected beam energy can be recycled using beam shapingoptics 114. Alternatively, or in addition, rejected beam energy can bedirected to the article processing unit 140 for heating or furtherpatterning. In certain embodiments, rejected beam energy can be directedto additional energy patterning systems or article processing units.

Image relay 120 receives a patterned image (typically two-dimensional)from the energy patterning unit 116 and guides it toward the articleprocessing unit 140. In a manner similar to beam shaping optics 114, theimage relay 120 can include optics to combine, focus, diverge, reflect,refract, adjust intensity, adjust frequency, or otherwise shape anddirect the patterned image.

Article processing unit 140 can include a walled chamber 148 and bed144, and a material dispenser 142 for distributing material. Thematerial dispenser 142 can distribute, remove, mix, provide gradationsor changes in material type or particle size, or adjust layer thicknessof material. The material can include metal, ceramic, glass, polymericpowders, other melt-able material capable of undergoing a thermallyinduced phase change from solid to liquid and back again, orcombinations thereof. The material can further include composites ofmelt-able material and non-melt-able material where either or bothcomponents can be selectively targeted by the imaging relay system tomelt the component that is melt-able, while either leaving along thenon-melt-able material or causing it to undergo avaporizing/destroying/combusting or otherwise destructive process. Incertain embodiments, slurries, sprays, coatings, wires, strips, orsheets of materials can be used. Unwanted material can be removed fordisposable or recycling by use of blowers, vacuum systems, sweeping,vibrating, shaking, tipping, or inversion of the bed 146.

In addition to material handling components, the article processing unit140 can include components for holding and supporting 3D structures,mechanisms for heating or cooling the chamber, auxiliary or supportingoptics, and sensors and control mechanisms for monitoring or adjustingmaterial or environmental conditions. The article processing unit can,in whole or in part, support a vacuum or inert gas atmosphere to reduceunwanted chemical interactions as well as to mitigate the risks of fireor explosion (especially with reactive metals).

Control processor 150 can be connected to control any components ofadditive manufacturing system 100. The control processor 150 can beconnected to variety of sensors, actuators, heating or cooling systems,monitors, and controllers to coordinate operation. A wide range ofsensors, including imagers, light intensity monitors, thermal, pressure,or gas sensors can be used to provide information used in control ormonitoring. The control processor can be a single central controller, oralternatively, can include one or more independent control systems. Thecontroller processor 150 is provided with an interface to allow input ofmanufacturing instructions. Use of a wide range of sensors allowsvarious feedback control mechanisms that improve quality, manufacturingthroughput, and energy efficiency.

FIG. 1B is a cartoon illustrating a bed 146 that supports material 144.Using a series of sequentially applied, two-dimensional patterned energybeam images (squares in dotted outline 124), a structure 149 isadditively manufactured. As will be understood, image patterns havingnon-square boundaries can be used, overlapping or interpenetratingimages can be used, and images can be provided by two or more energypatterning systems. In other embodiments, images can be formed inconjunction with directed electron or ion beams, or with printed orselective spray systems.

FIG. 2 is a flow chart illustrating one embodiment of an additivemanufacturing process supported by the described optical and mechanicalcomponents. In step 202, material is positioned in a bed, chamber, orother suitable support. The material can be a powder capable of beingmelted, fused, sintered, induced to change crystal structure, havestress patterns influenced, or otherwise chemically or physicallymodified to form structures with desired properties.

In step 204, unpatterned energy is emitted by one or more energyemitters, including but not limited to solid state or semiconductorlasers, or electrical power supply flowing electrons down a wire. Instep 206, the unpatterned energy is shaped and modified (e.g. intensitymodulated or focused). In step 208, this unpatterned energy ispatterned, with energy not forming a part of the pattern being handledin step 210 (this can include conversion to waste heat, or recycling aspatterned or unpatterned energy). In step 212, the patterned energy, nowforming a two-dimensional image is relayed toward the material. In step214, the image is applied to the material, building a portion of a 3Dstructure. These steps can be repeated (loop 218) until the image (ordifferent and subsequent image) has been applied to all necessaryregions of a top layer of the material. When application of energy tothe top layer of the material is finished, a new layer can be applied(loop 216) to continue building the 3D structure. These process loopsare continued until the 3D structure is complete, when remaining excessmaterial can be removed or recycled.

FIG. 3A is one embodiment of an additive manufacturing system 300 thatuses multiple semiconductor lasers as part of an energy patterningsystem 310. A control processor 350 can be connected to variety ofsensors, actuators, heating or cooling systems, monitors, andcontrollers to coordinate operation of multiple lasers 312, lightpatterning unit 316, and image relay 320, as well as any other componentof system 300. These connections are generally indicated by a dottedoutline 351 surrounding components of system 300. As will beappreciated, connections can be wired or wireless, continuous orintermittent, and include capability for feedback (for example, thermalheating can be adjusted in response to sensed temperature). The multiplelasers 312 can emit a beam 301 of light at a 1000 nm wavelength that,for example, is 90 mm wide by 20 mm tall. The beam 301 is resized byimaging optics 370 to create beam 303. Beam 303 is 6 mm wide by 6 mmtall, and is incident on light homogenization device 372 which blendslight together to create blended beam 305. Beam 305 is then incident onimaging assembly 374 which reshapes the light into beam 307 and is thenincident on hot cold mirror 376. The mirror 376 allows 1000 nm light topass, but reflects 450 nm light. A light projector 378 capable ofprojecting low power light at 1080p pixel resolution and 450 nm emitsbeam 309, which is then incident on hot cold mirror 376. Beams 307 and309 overlay in beam 311, and both are imaged onto optically addressedlight valve 380 in a 20 mm wide, 20 mm tall image. Images formed fromthe homogenizer 372 and the projector 378 are recreated and overlaid onlight valve 380.

The optically addressed light valve 380 is stimulated by the light(typically ranging from 400-500 nm) and imprints a polarization rotationpattern in transmitted beam 313 which is incident upon polarizer 382.The polarizer 382 splits the two polarization states, transmittingp-polarization into beam 317 and reflecting s-polarization into beam 315which is then sent to a beam dump 318 that handles the rejected energy.As will be understood, in other embodiments the polarization could bereversed, with s-polarization formed into beam 317 and reflectingp-polarization into beam 315. Beam 317 enters the final imaging assembly320 which includes optics 384 that resize the patterned light. This beamreflects off of a movable mirror 386 to beam 319, which terminates in afocused image applied to material bed 344 in an article processing unit340. The depth of field in the image selected to span multiple layers,providing optimum focus in the range of a few layers of error or offset.

The bed 390 can be raised or lowered (vertically indexed) within chamberwalls 388 that contain material 344 dispensed by material dispenser 342.In certain embodiments, the bed 390 can remain fixed, and optics of thefinal imaging assembly 320 can be vertically raised or lowered. Materialdistribution is provided by a sweeper mechanism 392 that can evenlyspread powder held in hopper 394, being able to provide new layers ofmaterial as needed. An image 6 mm wide by 6 mm tall can be sequentiallydirected by the movable mirror 386 at different positions of the bed.

When using a powdered ceramic or metal material in this additivemanufacturing system 300, the powder can be spread in a thin layer,approximately 1-3 particles thick, on top of a base substrate (andsubsequent layers) as the part is built. When the powder is melted,sintered, or fused by a patterned beam 319, it bonds to the underlyinglayer, creating a solid structure. The patterned beam 319 can beoperated in a pulsed fashion at 40 Hz, moving to the subsequent 6 mm×6mm image locations at intervals of 10 ms to 0.5 ms (with 3 to 0.1 msbeing desirable) until the selected patterned areas of powder have beenmelted. The bed 390 then lowers itself by a thickness corresponding toone layer, and the sweeper mechanism 392 spreads a new layer of powderedmaterial. This process is repeated until the 2D layers have built up thedesired 3D structure. In certain embodiments, the article processingunit 340 can have a controlled atmosphere. This allows reactivematerials to be manufactured in an inert gas, or vacuum environmentwithout the risk of oxidation or chemical reaction, or fire or explosion(if reactive metals are used).

FIG. 3B illustrates in more detail operation of the light patterningunit 316 of FIG. 3A. As seen in FIG. 3B, a representative input pattern333 (here seen as the numeral “9”) is defined in an 8×12 pixel array oflight projected as beam 309 toward mirror 376. Each grey pixelrepresents a light filled pixel, while white pixels are unlit. Inpractice, each pixel can have varying levels of light, includinglight-free, partial light intensity, or maximal light intensity.Unpatterned light 331 that forms beam 307 is directed and passes througha hot/cold mirror 376, where it combines with patterned beam 309. Afterreflection by the hot/cold mirror 376, the patterned light beam 311formed from overlay of beams 307 and 309 in beam 311, and both areimaged onto optically addressed light valve 380. The optically addressedlight valve 380, which would rotate the polarization state ofunpatterned light 331, is stimulated by the patterned light beam 309,311 to selectively not rotate the polarization state of polarized light307, 311 in the pattern of the numeral “9” into beam 313. The unrotatedlight representative of pattern 333 in beam 313 is then allowed to passthrough polarizer mirror 382 resulting in beam 317 and pattern 335.Polarized light in a second rotated state is rejected by polarizermirror 382, into beam 315 carrying the negative pixel pattern 337consisting of a light-free numeral “9”.

Other types of light valves can be substituted or used in combinationwith the described light valve. Reflective light valves, or light valvesbase on selective diffraction or refraction can also be used. In certainembodiments, non-optically addressed light valves can be used. These caninclude but are not limited to electrically addressable pixel elements,movable mirror or micro-mirror systems, piezo or micro-actuated opticalsystems, fixed or movable masks, or shields, or any other conventionalsystem able to provide high intensity light patterning. For electronbeam patterning, these valves may selectively emit electrons based on anaddress location, thus imbuing a pattern on the beam of electronsleaving the valve.

FIG. 3C is one embodiment of an additive manufacturing system thatincludes a switchyard system enabling reuse of patterned two-dimensionalenergy. Similar to the embodiment discussed with respect to FIG. 1A, anadditive manufacturing system 220 has an energy patterning system withan energy source 112 that directs one or more continuous or intermittentenergy beam(s) toward beam shaping optics 114. After shaping, the beamis two-dimensionally patterned by an energy patterning unit 230, withgenerally some energy being directed to a rejected energy handling unit222. Patterned energy is relayed by one of multiple image relays 232toward one or more article processing units 234A, 234B, 234C, or 234D,typically as a two-dimensional image focused near a movable or fixedheight bed. The bed (with optional walls) can form a chamber containingmaterial dispensed by material dispenser. Patterned energy, directed bythe image relays 232, can melt, fuse, sinter, amalgamate, change crystalstructure, influence stress patterns, or otherwise chemically orphysically modify the dispensed material to form structures with desiredproperties.

In this embodiment, the rejected energy handling unit has multiplecomponents to permit reuse of rejected patterned energy. Relays 228A,228B, and 22C can respectively transfer energy to an electricitygenerator 224, a heat/cool thermal management system 225, or an energydump 226. Optionally, relay 228C can direct patterned energy into theimage relay 232 for further processing. In other embodiments, patternedenergy can be directed by relay 228C, to relay 228B and 228A forinsertion into the energy beam(s) provided by energy source 112. Reuseof patterned images is also possible using image relay 232. Images canbe redirected, inverted, mirrored, sub-patterned, or otherwisetransformed for distribution to one or more article processing units.234A-D. Advantageously, reuse of the patterned light can improve energyefficiency of the additive manufacturing process, and in some casesimprove energy intensity directed at a bed, or reduce manufacture time.

FIG. 3D is a cartoon 235 illustrating a simple geometricaltransformation of a rejected energy beam for reuse. An input pattern 236is directed into an image relay 237 capable of providing a mirror imagepixel pattern 238. As will be appreciated, more complex pixeltransformations are possible, including geometrical transformations, orpattern remapping of individual pixels and groups of pixels. Instead ofbeing wasted in a beam dump, this remapped pattern can be directed to anarticle processing unit to improve manufacturing throughput or beamintensity.

FIG. 3E is a cartoon 235 illustrating multiple transformations of arejected energy beam for reuse. An input pattern 236 is directed into aseries of image relays 237B-E capable of providing a pixel pattern 238.

FIGS. 3F and 3G illustrates a non-light based energy beam system 240that includes a patterned electron beam 241 capable of producing, forexample, a “P” shaped pixel image. A high voltage electricity powersystem 243 is connected to an optically addressable patterned cathodeunit 245. In response to application of a two-dimensional patternedimage by projector 244, the cathode unit 245 is stimulated to emitelectrons wherever the patterned image is optically addressed. Focusingof the electron beam pattern is provided by an image relay system 247that includes imaging coils 246A and 246B. Final positioning of thepatterned image is provided by a deflection coil 248 that is able tomove the patterned image to a desired position on a bed of additivemanufacturing component 249.

In another embodiment supporting light recycling and reuse, multiplexmultiple beams of light from one or more light sources are provided. Themultiple beams of light may be reshaped and blended to provide a firstbeam of light. A spatial polarization pattern may be applied on thefirst beam of light to provide a second beam of light. Polarizationstates of the second beam of light may be split to reflect a third beamof light, which may be reshaped into a fourth beam of light. The fourthbeam of light may be introduced as one of the multiple beams of light toresult in a fifth beam of light. In effect, this or similar systems canreduce energy costs associated with an additive manufacturing system. Bycollecting, beam combining, homogenizing and re-introducing unwantedlight rejected by a spatial polarization valve or light valve operatingin polarization modification mode, overall transmitted light power canpotentially be unaffected by the pattern applied by a light valve. Thisadvantageously results in an effective re-distribution of the lightpassing through the light valve into the desired pattern, increasing thelight intensity proportional to the amount of area patterned.

Combining beams from multiple lasers into a single beam is one way toincreasing beam intensity. In one embodiment, multiple light beams, eachhaving a distinct light wavelength, can be combined using eitherwavelength selective mirrors or diffractive elements. In certainembodiments, reflective optical elements that are not sensitive towavelength dependent refractive effects can be used to guide amultiwavelength beam.

Patterned light can be directed using movable mirrors, prisms,diffractive optical elements, or solid state optical systems that do notrequire substantial physical movement. In one embodiment, amagnification ratio and an image distance associated with an intensityand a pixel size of an incident light on a location of a top surface ofa powder bed can be determined for an additively manufactured,three-dimensional (3D) print job. One of a plurality of lens assembliescan be configured to provide the incident light having the magnificationratio, with the lens assemblies both a first set of optical lenses and asecond sets of optical lenses, and with the second sets of opticallenses being swappable from the lens assemblies. Rotations of one ormore sets of mirrors mounted on compensating gantries and a final mirrormounted on a build platform gantry can be used to direct the incidentlight from a precursor mirror onto the location of the top surface ofthe powder bed. Translational movements of compensating gantries and thebuild platform gantry are also able to ensure that distance of theincident light from the precursor mirror to the location of the topsurface of the powder bed is substantially equivalent to the imagedistance. In effect, this enables a quick change in the optical beamdelivery size and intensity across locations of a build area fordifferent powdered materials while ensuring high availability of thesystem.

In certain embodiments, a plurality of build chambers, each having abuild platform to hold a powder bed, can be used in conjunction withmultiple optical-mechanical assemblies arranged to receive and directthe one or more incident energy beams into the build chambers. Multiplechambers allow for concurrent printing of one or more print jobs insideone or more build chambers. In other embodiments, a removable chambersidewall can simplify removal of printed objects from build chambers,allowing quick exchanges of powdered materials. The chamber can also beequipped with an adjustable process temperature controls.

In another embodiment, one or more build chambers can have a buildchamber that is maintained at a fixed height, while optics arevertically movable. A distance between final optics of a lens assemblyand a top surface of powder bed a may be managed to be essentiallyconstant by indexing final optics upwards, by a distance equivalent to athickness of a powder layer, while keeping the build platform at a fixedheight. Advantageously, as compared to a vertically moving the buildplatform, large and heavy objects can be more easily manufactured, sinceprecise micron scale movements of the build platform are not needed.Typically, build chambers intended for metal powders with a volume morethan ˜0.1-0.2 cubic meters (i.e., greater than 100-200 liters or heavierthan 500-1,000 kg) will most benefit from keeping the build platform ata fixed height.

In one embodiment, a portion of the layer of the powder bed may beselectively melted or fused to form one or more temporary walls out ofthe fused portion of the layer of the powder bed to contain anotherportion of the layer of the powder bed on the build platform. Inselected embodiments, a fluid passageway can be formed in the one ormore first walls to enable improved thermal management.

Improved powder handling can be another aspect of an improved additivemanufacturing system. A build platform supporting a powder bed can becapable of tilting, inverting, and shaking to separate the powder bedsubstantially from the build platform in a hopper. The powdered materialforming the powder bed may be collected in a hopper for reuse in laterprint jobs. The powder collecting process may be automated, andvacuuming or gas jet systems also used to aid powder dislodgement andremoval

Some embodiments of the disclosed additive manufacturing system can beconfigured to easily handle parts longer than an available chamber. Acontinuous (long) part can be sequentially advanced in a longitudinaldirection from a first zone to a second zone. In the first zone,selected granules of a granular material can be amalgamated. In thesecond zone, unamalgamated granules of the granular material can beremoved. The first portion of the continuous part can be advanced fromthe second zone to a third zone, while a last portion of the continuouspart is formed within the first zone and the first portion is maintainedin the same position in the lateral and transverse directions that thefirst portion occupied within the first zone and the second zone. Ineffect, additive manufacture and clean-up (e.g., separation and/orreclamation of unused or unamalgamated granular material) may beperformed in parallel (i.e., at the same time) at different locations orzones on a part conveyor, with no need to stop for removal of granularmaterial and/or parts.

In another embodiment, additive manufacturing capability can be improvedby use of an enclosure restricting an exchange of gaseous matter betweenan interior of the enclosure and an exterior of the enclosure. Anairlock provides an interface between the interior and the exterior;with the interior having multiple additive manufacturing chambers,including those supporting power bed fusion. A gas management systemmaintains gaseous oxygen within the interior at or below a limitingoxygen concentration, increasing flexibility in types of powder andprocessing that can be used in the system.

In another manufacturing embodiment, capability can be improved byhaving a 3D printer contained within an enclosure, the printer able tocreate a part having a weight greater than or equal to 2,000 kilograms.A gas management system may maintain gaseous oxygen within the enclosureat concentrations below the atmospheric level. In some embodiments, awheeled vehicle may transport the part from inside the enclosure,through an airlock, since the airlock operates to buffer between agaseous environment within the enclosure and a gaseous environmentoutside the enclosure, and to a location exterior to both the enclosureand the airlock.

Other manufacturing embodiments involve collecting powder samples inreal-time in a powder bed fusion additive manufacturing system. Aningester system is used for in-process collection and characterizationsof powder samples. The collection may be performed periodically and theresults of characterizations result in adjustments to the powder bedfusion process. The ingester system can optionally be used for one ormore of audit, process adjustments or actions such as modifying printerparameters or verifying proper use of licensed powder materials.

Yet another improvement to an additive manufacturing process can beprovided by use of a manipulator device such as a crane, lifting gantry,robot arm, or similar that allows for the manipulation of parts thatwould be difficult or impossible for a human to move is described. Themanipulator device can grasp various permanent or temporary additivelymanufactured manipulation points on a part to enable repositioning ormaneuvering of the part.

Referring to FIG. 4, in selected embodiments, a machine 410 may be adevice or system that executes a process of additive manufacture with atleast some level of autonomy. For example, a machine 410 may be orcomprise an additive manufacturing system 100, 300. In certainembodiments, the process of additive manufacture executed by a machine410 may comprise powder-bed fusion in the form of direct metal lasersintering (DMLS), electron beam melting (EBM), selective heat sintering(SHS), selective laser melting (SLM), selective laser sintering (SLS),or the like. At a manufacturing facility comprising multiple machines410, the processes of additive manufacture executed by the multiplemachines 410 may be independent of each other. Thus, different machines410 may start their respective processes at different times, manufacturethe same or different parts, and so forth.

In discussing machines 410 in accordance with the present invention, itmay be helpful to define a uniform coordinate system 411. Accordingly,certain machines 410 may correspond to or define longitudinal, lateral,and transverse directions 411 a, 411 b, 411 c orthogonal to one another.The longitudinal direction 411 a may correspond to a long axis of amachine 410. The lateral direction 411 b may combine with thelongitudinal direction 411 a to define a horizontal plane. That is, thelongitudinal and lateral directions may both extend within a horizontalplane. The transverse direction 411 b may extend up and down inalignment with gravity.

Machines 410 in accordance with the present invention may have anysuitable configuration. For example, in selected embodiments, a machine410 may comprise a powder-bed-fusion printer. Accordingly, a machine 410may include an energy patterning system 110, 310, an article processingunit 140, 340 (e.g., a sub-assembly comprising a dispenser 142 forselectively distributing layers of granular material 144, a buildplatform 146 or bed 146 over which various layers of the granularmaterial 144 may be distributed, various walls 148 positioned to containand/or support the various layers of the granular material 144, or thelike or a combination or sub-combination thereof), a controller 150, agantry system 412, or the like or a combination or sub-combinationthereof.

A gantry system 412 may include one or more longitudinal rails 414extending in the longitudinal direction 411 a, a carriage 416selectively moving in the longitudinal direction 411 a along the one ormore longitudinal rails 414, one or more lateral rails (not shown)forming part of the carriage 416, and a print head 418 selectivelymoving in the lateral direction 411 b along the one or more lateralrails. A print head 418 may comprise an energy patterning system 110,310 or some portion thereof. Relative motion in the transverse direction411 c between a print head 418 and a bed 146 (e.g., motion toaccommodate new layers of granular material 144 as they are laid down ona bed 146) may be accomplished by incrementally moving the print head418 away from the bed 146, incrementally moving the bed 146 away fromthe print head 418, or some combination thereof.

A machine 410 in accordance with the present invention may have anysuitable size. For example, the bed 146 of a machine 410 may extend fromabout 0.5 to about 12 meters in the longitudinal and/or lateraldirections 411 a, 411 b. Relative motion between a print head 418 and abed 146 and the sizing of various walls 148 may accommodate a buildup ofgranular material 144 from about 0.5 to about 5 meters.

Referring to FIG. 5, in selected embodiments, a machine 410 inaccordance with the present invention may enable or supportsubstantially continuous additive manufacture of parts that are long(e.g., continuous parts that are longer in the longitudinal direction411 a than the machine 410 can print in its printing range of motion).This may be accomplished by manufacturing a part in segments.

For example, in certain embodiments, a machine 410 in accordance withthe present invention may (1) manufacture a first segment of a part, (2)advance the part a selected distance down a conveyor 420, (3)manufacture a second segment of the part, (4) advance the part aselected distance down the conveyor 420, and (5) repeat until allsegments of the part have been completed. In this manner, additivemanufacture and clean-up (e.g., separation and/or reclamation of unusedor unamalgamated granular material 144) may be performed in parallel(i.e., at the same time) at different locations or zones on the conveyor420. Thus, additive manufacture in accordance with the present inventionneed not stop for removal of granular material 144 and/or parts.

In such embodiments, a bed 146 may form part of, be supported by, and/orride on a conveyor 420. A conveyor 420 may comprise one or more poweredrollers 422 that rotate as directed by a controller 150. Alternatively,a conveyor 420 may comprise a belt extending around a plurality ofrollers 422, one or more of which may be powered and rotate as directedby a controller 150. An energy patterning system 110, 310 or selectedcomponents thereof may be configured to move incrementally in thetransverse direction 411 c with respect to the conveyor 420. That is, amachine 410 may include a bed 146 that is fixed in the lateral andtransverse directions 411 b, 411 c and a print head 418 that indexes(e.g., incrementally moves) in the transverse direction 411 c to changethe focal point to accommodate new (i.e., higher) layers of material asthey are laid down on the bed 146.

As a granular material 144 is laid down, layer after layer, it may benecessary to contain the granular material 144 so that is does not move,shift, fall away from a part 410, or the like during additivemanufacture. Accordingly, a machine may include one or more walls 148.Certain walls 148 may be stationary. That is, they may not move with aconveyor 420. Other walls 148 may be traveling walls 148 that move witha conveyor 420. For example, in selected embodiments, two stationarywalls 148 may block granular material 144 from falling off the sides ofa conveyor 420 in a lateral direction 411 b, while two or more travelingwalls 148 may contain the granular material 144 in the longitudinaldirection 411 a.

After a completed segment of a part has been advanced down a conveyor420, a new process of additive manufacture may have a “clean slate” tobegin creating the next segment of the part. This new process mayinclude amalgamating selected granules to a near or trailing side of atraveling wall 148, thereby maintaining the longitudinal continuity(i.e., the continuous structural connection in the lateral direction 411a between a segment that is currently being formed and all previouslyformed segments) of the part. Thus, certain traveling walls 148 may formthe boundaries between the various segments of a part. Moreover, suchtraveling walls 148 may intersect any part that spans them. Accordingly,before a part is ready to use, selected portions of such walls 148 mayneed to be removed (e.g., broken off, cut off, ground off, or the like)from the part.

Thus, a machine 410 in accordance with the present invention may defineor include multiple zones. Different tasks may be performed in differentzones. In selected embodiments, different zones may correspond todifferent locations along a conveyor 420. Accordingly, a conveyor 420may advance a part through the various zones of a machine 410.

In certain embodiments, a machine 410 may include three zones. A firstzone may correspond to, include, or span the portion of a conveyor 420where additive manufacture occurs. Thus, a first zone may correspond tothe area on a conveyor 420 where the various layers of granular material144 are being laid down and granular material 144 is being maintained inintimate contact with a part.

A second zone may directly follow a first zone. A second zone may becharacterized by a significant portion of the unamalgamated portion of agranular material 144 moving away from a part. For example, in a secondzone, one or more walls 148 (e.g., stationary walls 148) may terminateso that the unamalgamated portion of a granular material 144 may nolonger be fully contained in the lateral direction 411 b. As a result,some of the unamalgamated portion of a granular material 144 may spilloff the sides of a conveyor 420. The spilling granular material 144 mayfall into one or more containers where it may be collected and reused.

In certain embodiments, some of the unamalgamated portion of a granularmaterial 144 may not “drain” off of a conveyor 420. Accordingly, withina second zone, this remainder of the granular material 144 may beremoved, cleaned-up, or the like in any suitable manner. For example, avacuum mechanism having a collection port that is controlled (e.g.,moved) manually or robotically may be used to collect the remainder.Alternatively, or in addition thereto, one or more flows of pressurizedgas that are controlled (e.g., aimed) manually or robotically may beused to dislodge the remainder from certain crevices, sweep theremainder off a conveyor 420, and/or move the remainder to one or morelocations where it can be accessed by a vacuum.

A third zone may directly follow a second zone. A third zone may becharacterized by a portion of a part within the third zone being exposedto view (e.g., completely, substantially, or partially exposed to viewby the removal or movement of a significant portion of the unamalgamatedportion of a granular material 144) without the part changing itsposition in the lateral and transverse directions 411 b, 411 c.

For example, in certain embodiments, a leading portion of a part mayreach a third zone while a trailing portion of the part is still beingmanufactured within the first zone. Accordingly, in selectedembodiments, a conveyor 420, a bed 146, one or more traveling walls 148,or the like or a combination or sub-combination thereof may cooperatingto maintain a leading portion of a part in the same position in thelateral and transverse directions 411 a, 411 c as the leading portionoccupied within the first zone and the second zone. Thus, the positionof the leading portion of the part may not excessively disrupt, distort,or the like additive manufacture that is occurring on a trailing portionof the part in the first zone.

Accordingly, a machine 410 that enables or supports substantiallycontinuous additive manufacture of parts that are long may itself belong. That is, the conveyor 420 of such a machine 410 may need to belonger than the longest part to be manufactured by the machine 410.

Referring to FIG. 6, a manufacturing facility in accordance with thepresent invention may comprise one or more work areas 424. A work area424 may be a space where one or more tasks corresponding to themanufacture of one or more parts are performed. A work area 424 mayinclude the tools, structures, materials, or the like needed to performthe one or more tasks associated therewith. Different work areas 424within a manufacturing facility may have different tasks associatedtherewith. In selected embodiments, the tasks associated with aparticular work area 424 may be those that reason or efficiency dictatesshould be performed together, adjacent one another in a particularsequence, or the like. For example, one particular work area 424 withina manufacturing facility may be tasked with creating a part usingpowder-bed fusion. Accordingly, that work area 424 may contain one ormore machines 410, a supply of granular material 144, and so forth.

Different work areas 424 may have different environmental requirements.When the requirements for a particular work area 424 differ from anatural environment (e.g., a typical temperature, pressure, gaseousmake-up, or the like), pose a threat to a natural environment, or thelike, the particular work area 424 may be contained within an enclosure426. An enclosure 426 may separate an environment corresponding to awork area 424 contained therewithin from one or more other environments.Accordingly, an enclosure 426 may control one or more environmentalconditions of a work area 424 as desired or necessary.

For example, certain granular materials 144 may be chemically sensitiveto the presence of oxygen (e.g., gaseous oxygen). Some, when in anoxygenated environment, pose a significant risk of explosion.Alternatively, or in addition thereto, oxygen may act as an oxidizingagent during a high temperature amalgamation of a granular material 144.The resulting oxidation may corrupt, harden, or otherwise adverselyaffect the structural and/or chemical properties of the part beingmanufactured.

Accordingly, in selected embodiments, an enclosure 426 corresponding tocertain powder-bed-fusion processes may enable one or more machines 410contained there within to operate in a environment with oxygen levelsbelow atmospheric levels by restricting an exchange of gaseous matterbetween an interior of the enclosure 426 and an exterior of theenclosure 426. In certain embodiments, this may be accomplished bymaking an enclosure 426 gas-tight or substantially gas-tight and fillingthe enclosure 426 with an inert or substantially inert gas such asnitrogen, argon, carbon-dioxide, other noble gas, or the like or acombination or sub-combination thereof. Accordingly, an enclosure 426may prevent or lower the risk of contamination due to oxidation and/orexplosion due to an increased reactivity of powdered materials. Inselected embodiments, all the various zones of a conveyor 420 may becontained within such an enclosure 426 (e.g., within a single enclosure426).

In certain embodiments, a low oxygen environment may be an environmentwhere the presence of gaseous oxygen is below a limiting oxygenconcentration (LOC). The LOC may be defined as the limitingconcentration of gaseous oxygen below which combustion is not possibleregardless of the concentration of fuel. The LOC may vary withtemperature, pressure, type of fuel (e.g., type of granular material144), type of inert gas, and concentration of inert gas. The LOCcorresponding to one enclosure 426 may be different than the LOC foranother enclosure 426. Thus, the concentration of gaseous oxygen withinany given enclosure 426 may be maintained below an LOC for thatenclosure 426 (i.e., an LOC that takes into account the temperature,pressure, type of granular material 144, type of inert gas, andconcentration of inert gas, etc. within that enclosure 426).

In other embodiments, a low oxygen environment may be an environmentwhere the presence of gaseous oxygen is well below an LOC. For example,a low oxygen environment may correspond to gaseous oxygen levels atabout 500 parts-per-million by volume or less, about 100parts-per-million by volume or less, about 50 parts-per-million byvolume or less, about 10 parts-per-million by volume or less, or about 1parts-per-million by volume or less. Accordingly, in selectedembodiments, a low oxygen environment in accordance with the presentinvention may be a substantially oxygen-free environment.

In certain embodiments, two or more work areas 424 may be connected viaone or more interface mechanisms 428. An interface mechanism 428 mayenable parts, material 144, personnel, or the like to pass smoothly andefficiently into and out of one or more work areas 424. In selectedembodiments, one or more interface mechanisms 428 may provide a path,railway, conveyor, or the like for parts, material 144, personnel, etc.to travel. Alternatively, or in addition thereto, one or more interfacemechanisms 428 may enable parts, material 144, personnel, or the like topass into and out of one or more enclosure 426 without compromising theenvironment (e.g., the low oxygen and inert gas environment) within theenclosure 426. Accordingly, in selected embodiments, an interfacemechanism 428 may include a door (e.g., a strip door). In otherembodiments where more separation is needed, an interface mechanism 428may include a pair of doors 430 a, 430 b that form a vestibule orantechamber. In still other embodiments where even more separation isneeded, an interface mechanism 428 may include an airlock bufferingbetween two incompatible environments (e.g., between an inert gaseousenvironment within an enclosure 426 and an active gaseous environmentoutside the enclosure 426).

An airlock may include at least two airtight (or substantially airtight)doors 430 a, 430 b. A first door 430 a of an airlock may enable parts,materials 144, personnel, or the like to pass between the interior ofthe airlock and the interior of the corresponding enclosure 426. Asecond door 430 b may enable parts, materials 144, personnel, or thelike to pass between the interior of the airlock and an exteriorenvironment surrounding the corresponding enclosure 426. An airlock mayalso include a gas exchange system that may purge and/or vent theairlock as desired or necessary to efficiently transition the gaseousenvironment within the airlock between a state compatible with theinterior of the enclosure 426 and a state compatible with theenvironment exterior to the enclosure 426.

In selected embodiments wherein an enclosure 426 contains one or moremachines 410, the number of machines 410 within the enclosure 426divided by the number of airlocks interfacing with the enclosure 426 maybe greater than one. Accordingly, multiple machines 410 within anenclosure 426 may share an airlock. That is, methods in accordance withthe present invention may include (1) removing from an enclosure 426through an airlock a first part manufactured by a first machine 410 in afirst process of additive manufacture and (2) removing from theenclosure 426 through the airlock a second part manufactured by a secondmachine 410 in a second process of additive manufacture, wherein thesecond processing is independent of the first process. In certainembodiments, the number of machines 410 within an enclosure 426 dividedby the number of airlocks interfacing with the enclosure 426 may begreater than two.

In general, the larger the airlock, the more expensive it may be tooperate in terms of time, equipment, materials, work, or the like.Accordingly, different airlocks corresponding to a particular enclosure426 may have different shapes and/or sizes. Thus, passing parts,material 144, personnel, or the like into and out of an enclosure 426may include selected the best airlock for the job.

For example, at least one relatively large airlock corresponding to anenclosure 426 may be large enough (e.g., have a length, width, andheight sufficient) to accommodate the largest part that will bemanufactured by a machine 410 within the enclosure 426, while anotherrelatively small airlock corresponding to the enclosure 426 may be justlarge enough to accommodate personnel passing into and out of theenclosure 426. Accordingly, if a human worker needs to enter anenclosure, he or she may do so most efficiently by using the relativelysmall airlock.

In certain embodiments, an enclosure 426 corresponding to a particularwork area 424 may include one or more gas management systems 432controlling the make-up of gaseous matter within an enclosure 426. Inselected embodiments, a gas management system 432 may maintainconcentrations of inert or substantially inert gas (e.g., nitrogen,argon, carbon-dioxide, or the like or a combination or sub-combinationthereof) above a desired level (e.g., argon at or above about 70% byvolume). Alternatively, or in addition thereto, a gas management systemmay maintain concentrations of oxygen and/or water vapor below desiredlevels (e.g., below 0.05% by volume for gaseous oxygen, below 0.05% byvolume for water vapor).

In selected embodiments, a gas management system 432 may include one ormore intake locations 434 and one or more outlet locations 436. A gasmanagement system 432 may take in gas from within an enclosure 426 atone or more intake locations 434. A gas management system 432 may outputgas into an enclosure 426 at one or more outlet locations 436. Incertain embodiments, wherein an enclosure 426 contains one or moremachines 410, one or more outlet locations 436 may be proximate the oneor more machines 410 (e.g., directly over the print beds 146 of one ormore machines 410) to provide a steady flow of inert gas thereto.

In certain embodiments, an enclosure 426 may include one or more windows438. A window 438 may enable one or more persons outside an enclosure426 to see and/or monitor what is happening inside the enclosure 426.Thus, one or more windows 438 may be important safety features of amanufacturing facility in accordance with the present invention.

If desired or necessary, one or more windows 438 may be configured tofilter out certain wavelengths of light that are incident thereon. Forexample, a window 438 may filter out certain wavelengths associated withone or more lasers of one or more machines 410 within an enclosure 426.Alternatively, or in addition thereto, a window 438 may filter outwavelengths associated with outside light that is attempting to enter anenclosure 426 thought the window 438. Thus, a window 438 may protectpersons outside an enclosure 426 and/or photosensitive materials oritems within the enclosure 426.

In certain embodiments, an enclosure 426 may be optically and/orthermally insulated. Optical insulation (e.g., radiation shielding) mayprevent certain wavelengths (e.g., wavelengths corresponding to thelasers of one or more machines 410) from escaping an enclosure. Thermalinsulation may be used to maintain (e.g., more easily maintain) adesired temperature within an interior of the enclosure 426. Forexample, certain processes of additive manufacture may require or runbetter at higher temperatures (e.g., temperatures greater than “roomtemperature” or greater than about 20 to about 25° C.). Such processesmay themselves also generate significant heat. Accordingly, an enclosure426 may be insulated in order to trap at least some of that heat.

An enclosure 426 in accordance with the present invention may be abuilding. Accordingly, in addition to restricting an exchange of gaseousmatter between an interior of the enclosure 426 and an exterior of theenclosure 426, the walls of an enclosure 426 may provide a weatherbarrier. Alternatively, an enclosure 426 may be housed within abuilding. Accordingly, the walls, roof, etc. of the building may providea weather barrier and leave the walls, ceiling, etc. of an enclosure 426to deal exclusively with restricting an exchange of gaseous matterbetween an interior of the enclosure 426 and an exterior of theenclosure 426, reducing a flow of heat between an interior of theenclosure 426 and an exterior of the enclosure 426, or the like. Thismay free an enclosure 426 to be constructed with materials, shapes,methods, or the like that may be incompatible with a weather barrier.

An enclosure 426 in accordance with the present invention may beconstructed in any suitable manner. For example, in selectedembodiments, an enclosure 426 may include one or more walls, ceilings,floors, or the like defining a generally rectangular shape or generallyrectangular sections of an overall shape. The floor may compriseconcrete (e.g., a sealed concrete surface). The walls and/or ceiling maycomprise modular metal sheets or panels that are bolted or otherwisefastened together. One or more sealants, gaskets, or the like may usedbetween adjoining sheets or panels to provide a gas-tight orsubstantially gas-tight seal. Alternatively, or in addition thereto, oneor more films, coatings, or the like may be used to provide a gas-tightor substantially gas-tight seal.

In certain embodiments, the gaseous environment within one or moreenclosures 426 may be incompatible with the respiratory requirements ofone or more humans that may need to enter and/or work within theenclosure 426. Accordingly, to work within certain enclosures 426 inaccordance with the present invention, one or more workers may donpersonal protective equipment (PPE). Thereafter, when the worker entersan enclosure 426, the PPE may create a barrier between the worker andthe working environment within the enclosure 426.

In selected embodiments, the PPE worn by one or more workers may includea self-contained breathing apparatus (SCBA). A SCBA may be a closedcircuit device that filters, supplements, and recirculates exhaled gas(e.g., a rebreather). Alternatively, SCBA may be an open circuit devicethat exhausts at least some exhaled gas (e.g., nitrogen, carbon dioxide,oxygen, water vapor, or a combination or sub-combination thereof) into asurrounding environment. In embodiments where an open circuit device isused, the amount exhaled by the one or more workers within an enclosure426 may be quite small with respect to the over size of the enclosure426. Accordingly, the release of oxygen, water vapor, or the like intothe interior of the enclosure 426 may be sufficiently small as to benegligible or at least within acceptable limits (e.g., within thecapacity of a gas management system 432 to rectify).

In certain embodiments, a SCBA may include a full face mask. If desiredor necessary, such a mask may be configured to filter out certainwavelengths of light that are incident thereon. For example, a mask mayfilter out certain wavelengths associated with one or more lasers of oneor more machines 410 within an enclosure 426. Thus, a mask may protect aworker operating within an enclosure 426 from incidental laser exposure,which is typically due to reflections, but may be to a misaligned systemor a system undergoing an alignment procedure.

In selected embodiments, the PPE worn by one or more workers within anenclosure 426 may protect the workers from potential thermal and/orlaser exposure. For example, when operating in an environment forpowder-bed fusion, a worker may be exposed to high temperatures.Accordingly, the PPE for that worker may include a protective thermalsuit (e.g., a suit that is or is like the structural turnout gear wornby firefighters).

Referring to FIGS. 7 and 8, in selected embodiments, the ratio of workareas 424 to enclosures 426 within at least a portion of a manufacturingfacility may be one to one. That is, within at least a portion of amanufacturing facility, every work area 424 may be contained within itsown dedicated enclosure 426. However, in other embodiments or otherportions of a manufacturing facility, the number of work areas 424divided by the number of enclosures 426 may be greater than one.

For example, in selected embodiments, the environment needed for onework area 424 a may be substantially identical to or at least compatiblewith the environment needed for one or more other work areas 424 b.Accordingly, if desired, those multiple work areas 424 a, 424 b may becontained within the same enclosure 426. An example of multiple workareas 424 a, 424 b that may be contained within one enclosure mayinclude an area 424 a were one or more parts are created by powder-bedfusion using a granular material 144 and an area 424 b wereunamalgamated portions of the granular material 144 are removed andrecycled. Another example of two such work areas 424 may include an area424 were one or more parts are created by powder-bed fusion using agranular material 144 and unamalgamated portions of the granularmaterial 144 are removed and recycled and an area 424 where the granularmaterial 144 is used as a shot media in a peening process.

Alternatively, or in addition thereto, certain work areas 424 f may notneed an enclosure 426. For example, certain work areas 424 f may befully compatible with an outdoor environment. Alternatively, those workareas 424 f may be fully compatible with the typical environment foundwithin a factory building. They may not need any environmentalconditioning beyond the weather barrier that a building provides. Thismay be true even when one or more nearby or adjacent work areas 424 ewithin the factory building do need an additional enclosure 426 (e.g.,do need additional environmental conditioning beyond what a buildingprovides). Accordingly, certain work areas 424 within at least a portionof a manufacturing facility may not be contained within any enclosure426, may not be contained within any enclosure 426 other than a buildingproviding a weather barrier, or the like.

Referring to FIG. 9, in selected embodiments, a manufacturing facilitymay comprise multiple work areas 424 connected by one or more interfacemechanisms 428 to form a network 440. One or more of the work areas 424forming such a network 440 may be contained within enclosures 426. Oneor more of the work areas 424 forming such a network 440 may not need anenclosure 426 and, therefore, may not be contained within one. One ormore of the work areas 424 forming such a network 440 may be containedwithin one or more buildings. For example, in selected embodiments, allof the various work areas 424 forming a network 440 may be containedwithin a single building. In such embodiments, any work areas 424contained within enclosures 426 may be work areas 424 that require moreenvironmental conditioning than that provided by the building.

The various work areas 424 of a network 440 may be defined and/orarranged to correspond to certain manufacturing-related processes. Suchprocesses may include creating parts via additive manufacture; removalof parts from the machines 410 that created them; removal ofunamalgamated granular material 144; separating parts from a base or bed146, one or more support structures (e.g., exterior portions of one ormore traveling walls that extend through a part, one or more temporarystructures printed to support a part during additive manufacture thatwill not be included within the finished part, etc.), or the like; heattreating; peening; powder coating, painting, anodizing, or the like;packaging for shipment; or the like or a combination or sub-combinationthereof.

For example, in selected embodiments, a network 440 may include a firstwork area 424 a for powder-bed fusion in an inert environment providedby an enclosure 426, a second work area 424 b for removing granularmaterial 144 from a build platform 146 in an enclosure 426, a third workarea 424 c for shot peening to improve surface finish in an enclosure426, a fourth work area 424 d for heat treating to anneal metal parts inan enclosure 426, a fifth work area 424 e for removing parts from thebuild platform 146 in an enclosure 426, a sixth work area 424 f forpacking and shipping, or the like or a combination or sub-combinationthereof.

In a first work area 424 a, one or more machines 410 may be containedwithin an enclosure 426. The machines 410 may all be the same size or ofvarying sizes. Similarly, the one or more machines 410 may all be thesame type or of varying types. For example, in selected embodiments,each of the one or more machines 410 within an enclosure 426 mayamalgamate (e.g., unite, bond, fuse, sinter, melt, or the like) aparticular granular material 144 in a batch process (e.g., in a processexecuted by a machine 410 corresponding to FIG. 4). In otherembodiments, each of the one or more machines 410 within an enclosure426 may amalgamate a particular granular material 144 in a continuousprocess (e.g., in a process executed by a machine 410 corresponding toFIG. 5). In still other embodiments, one or more machines 410 within anenclosure 426 may amalgamate a particular granular material 144 in abatch process, while one or more other machines 410 within the enclosure426 may amalgamate the particular granular material 144 in a continuousprocess.

One or more machines 410 of a first work area 424 a may be arranged sothat sufficient space around the machines 410 is preserved for one ormore human workers, robots, or the like to access the machines 410,remove parts therefrom, vacuum up unamalgamated granular material 144for reuse, or the like. Alternatively, or in addition thereto, a firstwork area 424 a may include various gantries, catwalks, or the like thatenable one or more human workers, robots, or the like to access themachines 410 (e.g., visually access, physical access) from above. Thismay be helpful when a first work area 424 a includes one or more largemachines 410 where access from the edges or sides thereof may beinsufficient for certain tasks.

An enclosure 426 corresponding to or containing a first work area 424 amay maintain concentrations of inert or substantially inert gas (e.g.,nitrogen, argon, carbon-dioxide, or the like or a combination orsub-combination thereof) above a desired level (e.g., argon at or aboveabout 70% by volume). Alternatively, or in addition thereto, anenclosure 426 corresponding to or containing a first work area 424 a maymaintain concentrations of oxygen and/or water vapor below desiredlevels (e.g., below 0.05% by volume for gaseous oxygen, below 0.05% byvolume for water vapor).

In a second work area 424 b, unamalgamated granular material 144 may beremoved from a build platform 146 through various methods. For example,a vacuum mechanism having a collection port that is controlled (e.g.,moved) manually or robotically may be used to collect unamalgamatedgranular material 144 from around a part, off a build platform 146 orbed 146 or the like. Alternatively, or in addition thereto, one or moreflows of pressurized gas that are controlled (e.g., aimed) manually orrobotically may be used to dislodge the unamalgamated granular material144 from certain crevices, sweep the unamalgamated granular material 144off a build platform 146 or bed 146, and/or move the unamalgamatedgranular material 144 to one or more locations where it can be accessedby a vacuum.

An enclosure 426 corresponding to or containing a second work area 424 bmay maintain concentrations of inert or substantially inert gas (e.g.,nitrogen, argon, carbon-dioxide, or the like or a combination orsub-combination thereof) above a desired level (e.g., argon at or aboveabout 70% by volume). Alternatively, or in addition thereto, anenclosure 426 corresponding to or containing a second work area 424 bmay maintain concentrations of oxygen and/or water vapor below desiredlevels (e.g., below 0.05% by volume for gaseous oxygen, below 0.05% byvolume for water vapor).

In selected embodiments, first and second work areas 424 a, 424 b may becontained within separate enclosures 426 as illustrated. In otherembodiments, first and second work areas 424 a, 424 b may be containedwithin the same enclosure 426. Moreover, in certain embodiments (e.g.,embodiments corresponding to a batch process using a machine 410 likethe one shown in FIG. 4), first and second work areas 424 a, 424 b maygeographically overlap to at least some degree, but may be temporallyspaced in time (e.g., one or more tasks corresponding to one work area424 a may be performed at a different time than one or more taskscorresponding to the other work area 424 b).

Alternatively, in other embodiments (e.g., embodiments corresponding toa continuous process using a machine 410 like the one shown in FIG. 5),first and second work areas 424 a, 424 b may be geographically adjacentone another, but may temporally overlap to some degree (e.g., one ormore tasks corresponding to one work area 424 a may be performed at thesame time as one or more tasks corresponding to the other work area 424b). In such embodiments, a first zone of a machine 410 may correspond toor be a first work area 424 a and a second zone (or a combination of thesecond and third zones) may correspond to or be a second work area 424b.

In a third work area 424 c, a peening process may be manually orrobotically applied to one or more parts. For example, in selectedembodiments, a manual or robotic system may use the same granularmaterial 144 (i.e., the same granular material 144 used to create theparts) as a shot media in a peening process to improve a surface finishof the parts. Accordingly, an enclosure 426 corresponding to orcontaining a third work area 424 c may maintain concentrations of inertor substantially inert gas (e.g., nitrogen, argon, carbon-dioxide, orthe like or a combination or sub-combination thereof) above a desiredlevel (e.g., argon at or above about 70% by volume). Alternatively, orin addition thereto, an enclosure 426 corresponding to or containing athird work area 424 c may maintain concentrations of oxygen and/or watervapor below desired levels (e.g., below 0.05% by volume for gaseousoxygen, below 0.05% by volume for water vapor).

In a fourth work area 424 d, an enclosure 426 may be or comprise an ovenfor heat treating one or more parts. Such an enclosure 426 may,therefore, be configured to generate, retain, and control significantamounts of heat. The exact amount of heat may vary between the size ofthe enclosure 426, the nature of the parts being heat treated, and thelike. If desired or necessary, such an enclosure 426 may also maintainconcentrations of inert or substantially inert gas (e.g., nitrogen,argon, carbon-dioxide, or the like or a combination or sub-combinationthereof) above a desired level (e.g., argon at or above about 70% byvolume). Alternatively, or in addition thereto, an enclosure 426corresponding to or containing a fourth work area 424 d may maintainconcentrations of oxygen and/or water vapor below desired levels (e.g.,below 0.05% by volume for gaseous oxygen, below 0.05% by volume forwater vapor).

In a fifth work area 424 e, one or more build platforms 146 or beds 146may be separated from the parts they supported, one or more exteriorportions of one or more traveling walls that extend through parts may beremoved, one or more temporary structures printed to support partsduring additive manufacture that will not be included within thefinished parts may be removed, or the like or a combination thereof. Inselected embodiments, this may involve wire electrical dischargemachining (EDM) process. In such embodiments, parts may be submergedwithin a bath of partially de-ionized water where the ion content iscarefully controlled as part of the EDM process. An enclosure 426 for afifth work area 424 e may be included or omitted as desired ornecessary.

In a sixth work area 424 f, one or more parts may be prepared forshipping and/or shipped. For example, in a sixth work area 424 f, one ormore parts may be painted, packaged, wrapped with plastic, secured toone or more pallets, or the like and loaded on a truck for shipment. Anenclosure 426 for a sixth work area 424 f may be included or omitted asdesired or necessary.

In selected embodiments, a network 440 may comprise a plurality of workareas 424 connected in series by one or more interface mechanisms 428.Such interface mechanisms 428 may enable one or more parts to flowsmoothly and efficiently from one work area 424 to the next.Accordingly, the work areas 424 may be arranged in the network 440 sothat the tasks associated therewith may be performed in the required ordesired order.

Referring to FIG. 10, in certain embodiments, a network 440 may comprisea plurality of work areas 424 connected in a non-sequential manner byone or more interface mechanisms 428. Such interface mechanisms 428 mayenable one or more parts to flow smoothly and efficiently from any workarea 424 within the network 440 to any other work area 424 within thenetwork 440. In selected embodiments, a non-sequential network 440 mayinclude a hub 442. A hub 442 may comprise a path, intersection of rails,enclosure 426, or the like or a combination or sub-combination thereofthat smoothly and efficiently interfaces between various interfacemechanisms 428. Accordingly, a part may pass from one work area 424,through an interface mechanism 428 to a hub 442, through the hub 442 toanother interface mechanism 428, and through that interface mechanism428 to another work area 424.

Referring to FIG. 11, in certain embodiments, a network 440 may comprisea plurality of work areas 424 connected in both a sequential manner anda non-sequential manner by one or more interface mechanisms 428.Accordingly, such a network 440 may provide the benefits of both typesof networks 440.

Referring to FIGS. 12 and 13, in selected embodiments, a network 440 mayinclude one or more vehicles 444. A vehicle 444 may provide a mechanismfor supporting and transporting one or more parts 446 through a network440 (e.g., into and out of one or more work areas 424, through one ormore interface mechanisms 428, through one or more hubs 442, or the likeor a combination thereof). That is, certain parts 446 (particularly whencombined with build platforms 146 or beds 146 and/or traveling walls 448or other temporary structures) may be quite large and/or heavy (e.g.,weigh over 2,000 kilograms.). Accordingly, vehicles 444 may facilitatethe transport of those parts 446.

Vehicles 444 in accordance with the present invention may operate in anysuitable manner. For example, vehicles 444 may transport print beds 146,parts 446, or other materials by rolling or otherwise moving over a path(e.g., a concrete floor), conveyor system, rail, or combination ofmultiple rails using traditional railroad concepts, linear movement on atrack using an encoder, linear motion provided by a pulley system,motion and/or levitation provided by magnetic levitation rails, motionvia a conveyor system or belt, or the like or a combination orsub-combination thereof.

Accordingly, in selected embodiments, a vehicle 444 may have wheels 450that roll on a supporting surface 452. A support surface 452 may be afloor (e.g., a floor having a visually, electronically, or magneticallydetectable path applied thereto or embedded therewithin). A supportsurface 452 may also be one or more rails. Such rails may be locatedbelow a part 446 being carried by a vehicle 444. Alternatively, suchrails may be located above a part 446 being carried by a vehicle 444.That is, the rails may be overhead rails and a vehicle 44 may becarriage or trolley rolling on the overhead rails while suspending apart 446 therebelow.

The supporting surface 452 over which a vehicle 444 may roll may extendinto and out of one or more work areas 424, through one or moreinterface mechanisms 428, through one or more hubs 442, or the like or acombination thereof. Accordingly, each section of a supporting surface452 may be part of a work area 424, an interface mechanism 428, a hub442, or the like. This may enable a vehicle 444 to transport, in one ormore trips, one or more parts 446 from inside an enclosure 426 (e.g.,one or more parts 446 created by one or more machines 410 located withinthe enclosure 426), through an interface mechanism 428 (e.g., through anairlock as the airlock operates to buffer between a gaseous environmentwithin the enclosure and a gaseous environment outside the enclosure),and to a location exterior to both the enclosure 426 and the interfacemechanism 428 (e.g., to a location corresponding to another work area424, to a location within another enclosure 426, to a location within ahub 442, or to some other location). Moreover, this may enable thevehicle 444 to continuously support the weight of the one or more parts446 (e.g., weight of 2,000 kilograms. or greater per part) during suchtransport.

In selected embodiments, one or more doors 430 of an interface mechanism428 may be configured to seal against a supporting surface 452. Forexample, if a support surface 452 comprises a rail, one or more doors430 of an interface mechanism 428 may have a sealing element shaped toselectively abut and seal against that rail. Thus, vehicles 444 may passthrough, into, and/or out of one or more interface mechanisms 428 asthey perform their intended functions (e.g., as they function as anairlock)

A vehicle 444 in accordance with the present invention may be controlledand/or operated manually, automatically, autonomously, orsemi-autonomously. For example, in selected embodiments, one or morevehicles 444 may be pushed and/or steered by one or more humanoperators. In other embodiments, various on-board or off-board controlsystems may sense what is happening with respect to a vehicle 444 andinstruct the vehicle 444 when to move, when to stop, how to steer, andthe like.

In selected embodiments, a vehicle 444 may include various features thatfacilitate loading and unloading one or more parts 446. For example, inselected embodiments, a vehicle 44 may include one or more rollers 454.This may enable large and/or heavy parts 446 to roll onto the vehicle444 without sliding or lifting. Additionally, a vehicle 44 may have aheight 456 that matches one or more other components within a network440 (e.g., that matches the height of a conveyor 420 of a machine 410)so that exchanges (e.g., exchanges of parts 446) between the vehicle 444and those components can be performed without lifting. Alternatively, avehicle 444 may have an adjustable height 456 so that it can interfacewith various components having various heights.

In the above disclosure, reference has been made to the accompanyingdrawings, which form a part hereof, and in which is shown by way ofillustration specific implementations in which the disclosure may bepracticed. It is understood that other implementations may be utilizedand structural changes may be made without departing from the scope ofthe present disclosure. References in the specification to “oneembodiment,” “an embodiment,” “an example embodiment,” “selectedembodiments,” “certain embodiments,” etc., indicate that the embodimentor embodiments described may include a particular feature, structure, orcharacteristic, but every embodiment need not necessarily include theparticular feature, structure, or characteristic. Moreover, such phrasesare not necessarily referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with an embodiment, it is submitted that it is within theknowledge of one skilled in the art to apply such feature, structure, orcharacteristic to other embodiments whether or not explicitly described.

1. A method of additive manufacture, the method comprising: operating amanufacturing facility comprising a first enclosure, a first machinecontained within the first enclosure, a first gas management system, andan airlock, the airlock comprising an interior, a first door interfacingbetween the interior of the airlock and an interior of the firstenclosure, and a second door interfacing between the interior of theairlock and an area exterior to the first enclosure; creating, by thefirst machine during the operating, a first part via a first processcomprising additive manufacture using an energy beam to amalgamateselected portions of a powder located within the first enclosure;maintaining, by the first gas management system during the creating,gaseous oxygen within the first enclosure below atmospheric levels;transporting the first part from inside the first enclosure, through theairlock as the airlock operates to buffer between a gaseous environmentwithin the first enclosure and a gaseous environment outside the firstenclosure, and to the area; and continuously supporting the first partduring the transporting.
 2. The method of claim 1, wherein: the firstpart has a weight; and the continuously supporting comprisescontinuously supporting, by a vehicle, conveyor system, railway, or beltduring the transporting, the weight of the first part from inside thefirst enclosure, through the airlock, and to the area.
 3. The method ofclaim 2, further comprising performing proximate the area a secondprocess corresponding to manufacture of the first part, wherein thesecond process comprises removal of unamalgamated powder, heattreatment, peening, cutting, or painting.
 4. The method of claim 3,wherein the area is within a second enclosure.
 5. The method of claim 4,further comprising maintaining, by a second gas management system duringthe performing, gaseous oxygen within the second enclosure at or below alimiting oxygen concentration.
 6. The method of claim 5, wherein: thevehicle is a wheeled vehicle; and the transporting comprises rolling, bythe wheeled vehicle, over a supporting surface.
 7. The method of claim6, wherein the supporting surface is a floor.
 8. The method of claim 6,wherein the supporting surface is at least one rail located below thefirst part.
 9. The method of claim 6, wherein the supporting surface isat least one rail located above the first part.
 10. The method of claim1, wherein the transporting comprises rolling, by a wheeled vehicle,over a floor, at least one rail located below the first part, or atleast one rail located above the first part.
 11. The method of claim 10,further comprising removing from the first enclosure through the airlocka second part manufactured by a second machine in a second processcomprising additive manufacture, the second process being independent ofthe first process.
 12. The method of claim 11, wherein the removingcomprises transporting, by the wheeled vehicle, the second part frominside the first enclosure, through the airlock as the airlock operatesto buffer between the gaseous environment within the first enclosure andthe gaseous environment outside the first enclosure, and to the area.13. The method of claim 12, wherein: the second part has a weight; andthe method further comprises continuously supporting, by the wheeledvehicle, the weight of the second part during the transporting of thesecond part from inside the first enclosure, through the airlock, and tothe area.
 14. The method of claim 1, further comprising assisting, by ahuman contained completely within the first enclosure, in removingunamalgamated powder from around the first part.
 15. The method of claim14, further comprising wearing, by the human during the assisting, aself contained breathing apparatus.
 16. The method of claim 1, whereinthe first process comprises: distributing a first layer of the powder;directing radiant energy at a first subset of granules within the firstlayer; distributing a second layer of the powder over the top of thefirst layer; and directing radiant energy at a second subset of granuleswithin the second layer.
 17. The method of claim 16, wherein the firstprocess further comprises: melting or sintering the first subset ofgranules; and melting or sintering the second subset of granules. 18.The method of claim 17, wherein the first process further comprises:assisting, by a human contained completely within the first enclosure,in removing unamalgamated granules of the powder from around the firstpart; and wearing, by the human during the assisting, a self containedbreathing apparatus.
 19. A method of additive manufacture, the methodcomprising: operating a manufacturing facility comprising an enclosure,a first machine contained within the enclosure, a second machinecontained within the enclosure, a gas management system, and an airlock,the airlock comprising an interior, a first door interfacing between theinterior of the airlock and an interior of the enclosure, and a seconddoor interfacing between the interior of the airlock and an areaexterior to the enclosure; creating, by the first machine during theoperating, a first part via a first process comprising amalgamatingselected portions of a first quantity of powder located within theenclosure; creating, by the second machine during the operating, asecond part via a second process independent of the first process, thesecond process comprising amalgamating selected portions of a secondquantity of powder located within the enclosure; maintaining, by the gasmanagement system during the creating of the first and second parts,gaseous oxygen within the enclosure below atmospheric level; conveyingthe first part out of the enclosure through the airlock as the airlockoperates to buffer between a gaseous environment within the firstenclosure and a gaseous environment outside the first enclosure; andconveying the second part out of the enclosure through the airlock asthe airlock operates to buffer between the gaseous environment withinthe first enclosure and the gaseous environment outside the firstenclosure.
 20. The method of claim 19, wherein: the conveying the firstpart comprises continuously supporting, by a vehicle, conveyor system,railway, or belt, a weight of the first part as the first part movesfrom inside the first enclosure, through the airlock, and to the area;and the conveying the second part comprises continuously supporting, bythe vehicle, conveyor system, railway, or belt, a weight of the secondpart as the second part moves from inside the first enclosure, throughthe airlock, and to the area.